Question

In a recent test, you scored 1.0 standard deviations above the average score attained, and the scores are normally distributed. What percentage of students scored lower than you?

Answer 1

97.75 %

Explanation:

You score 1 standard deviation above the mean

a) we have from left tail up to the mean 50 % of all values

b) We have in the interval [ μ - σ ; μ + σ ] 95.5 % of all possible values, if we divide that 95.5 by 2 we get 47.75 %, the part of the values that correspond to the right, then in order to get the % of students scored lower we add

50 + 47.75 = 97.75 %

So you can say that the porcentage of students that scored lower than you is 97.75 %